I have an old swiss army knife that I use on all arrows. It is dull enough that it won't cut into carbon, and will still take everything off. I will usually scrape it real good one time, then soak a paper towel in acetone and rub it down real well, then scrape again to get any remnants off, then wipe one more time w/ the paper towel. They end up clean as a whistle and ready to fletch again.